On the container question there was an item on Sky News about containers that had been converted to be full homes... nice and portable, like a caravan without wheels. They started at $12k but I would presume that includes a bathroom, toilet, kitchen etc.
I reckon if you could get one of the half sized ones for $1.5 to $2.5k, line it, connect power, air conditioning etc. for another $1k you would be looking at quite an economical option.